Bag-making machine



July 23, 1968 H. MEMBRINO 3,393,493

BAG-MAKING MACHINE Original Filed Aug. 16, 1963 6 Sheets-Sheet 1 July23, 1968 H. MEMBRINO 3,393,493

BAG-MAKING MACHINE E 0* is E HERCULES MEMBRINO July 23, 1968 H. MEMBRlNO3,393,493

BAG-MAKING MACHINE Original Filed Aug. 16, 1965 6 Sheets-Sheet 5 Fig. 42

July 23, 1968 H. MEMBRINO BAG-MAKING MACHINE 6 Sheets-Sheet 5 OriginalFiled Aug. 16, 1963 Hulk";

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HERCULES MEMBRlNO July 23, 1968 MEMBRINO 3,393,493

BAG-MAKING MACHINE Original Filed Aug. 16, 1963 6 Sheets-Sheet Y a Fig./4

I74 QMW HERCULES MEMBRINO MWW United States Patent 3,393,493 BAG-MAKINGMACHINE Hercules Membrino, 1934 Arch St., Philadelphia, Pa. 19103Original application Aug. 16, 1963, Ser. No. 302,521, now Patent No.3,233,527. Divided and this application Oct. 15, 1965, Ser. No. 496,369

7 Claims. (Cl. 53-183) ABSTRACT OF THE DISCLOSURE A bag-making machinecomprising a support structure supporting a single rotatable heatsealing and cutting element backed by a rotatable impression roller, theheat sealing and cutting element ada-pted to form lines of seal withspaced interruptions in a double ply thermoplastic strip as the stripmoves from a supply roll. The interruptions form connecting meansbetween the bags formed from the strip by the heat sealing and cuttingelement. As the connected bags continue to move through the machine,they pass a fillin-g station where a filler is inserted sidewise betweenthe sealed edges of the bags. If the strip has two overfolded plys,there is a side opening for the filler, but if the strip is tubular, acutting means is provided at the filling station to automatically cut anopening just before the filler is inserted. There is also preferably aspreading means, including a blower adapted to blow air into the bags,for spreading the lips of the side opening prior to insertion of thefiller.

This invention relates to a machine for making bags, and it particularlyrelates to a machine .for making bags of thermoplastic polyolefinmaterials such as polyethylene, polypyropylene, polyvinyl alcohol,polyvinyl acetate, etc.

This is a division of apaplicants co-pending application Ser. No.302.521, filed Aug. 16, 1963.

Plastic bags are assuming an ever greater popularity for a variety ofdifferent uses such as the packaging of shirts and other clothing, thepackaging of loose items such as nuts and bolts, the use in the home forwrapping sandwiches, baked goods, meats, frozen foods and other similaritems, and many other uses too numerous to enumerate.

In order to meet the increasing popular demand at an acceptable price,it has become necessary to produce these bags in the most economical andrapid manner possible. This necessitates the utilization of a machinewhich is capable of continuous and rapid operation and which can beoperated by unskilled or at the most only semiskilled labor.

It is one object of the present invention to provide a machine whichfulfills all of the aforesaid requirements of easy, rapid and economicaloperation.

Another object of the present invention is to provide a machine of theaforesaid type which is equally adapted to work continuously orintermittently.

Another object of the present invention is to provide a machine of theaforesaid type which is capable of easy adjustment to operate on bags ofdifferent sizes.

Another object of the present invention is to provide a machine of theaforesaid type which is adapted to work on raw stock of either thetubular or laminated sheet type.

Another object of the present invention is to provide a machine of theaforesaid type which is adapted to fill the bags while they are beingmade.

Other objects and many of the attendant advantages of this inventionwill be readily appreciated as the same "ice becomes better understoodby reference to the following descrip-tion when read in conjunction withthe accompanying drawings wherein:

FIG. 1 is a side elevational view of a machine embodying the presentinvention.

FIG. 2 is an enlarged, detailed, side elevational view of the portion oft-he machine shown at the right in FIG. 1.

FIG. 3 is a side elevational view of the opposite side of the machinefrom that shown in FIG. 2.

FIG. 4 is a top plan view, with parts broken away, of the mechanism ofFIG. 2.

FIG. 5 is a sectional view taken on line 5-5 of FIG. 4.

FIG. 6 is a sectional view, with parts broken away, taken on line 6-6 ofFIG. 5.

FIG. 7 is a fragmentary sectional view taken on line 7-7 of FIG. 5.

FIG. 8 is an exploded perspective view showing the differential gearmechanism for controlling the positions of the bags in the machine asthey pass therethrough.

FIG. 9 is an enlarged, detailed, top perspective view of the portion ofthe machine which is situated at the left in FIG. 1.

FIG. 10 is a sectional view taken on line 10-10 of FIG. 9.

FIG. 11 is a cross-sectional view taken on line 11-11 of FIG. 9'.

FIG. 12 is an enlarged, detailed, side elevational view of the bagopening and nipping means shown in FIG. 9.

FIG. 13 is a fragmentary, side elevational view showing a modificationof the machine wherein it is used to form separate bags arranged instacks.

FIG. 14 is a top plan view of the mechanism 'of FIG. 13.

FIG. 15 is a side elevational view showing a modification of the machinewherein the bags are retained in a strip but are rolled up in a roll.

Referring now in greater detail to the various figures of the drawingswherein similar reference characters refer to similar parts, there isshown in FIG. 1 an assembly view of the preferred embodiment of theinvention, the entire assembly being generally designated 10, Theassembly 10 comprises an initial forming mechanism, generally designated12, and a filling, finishing and stacking mechanism, generallydesignated 14.

The mechanism 12 comprises a framework 16 including a side plate 18 (seeFIG. 2) and an opposite side plate 20 (see FIG. 3). Between the sideplates 18 and 20 extends a main drive shaft 22 having a pulley 24 at oneend. Also mounted on the shaft 22 coaxial with pulley 24 is a sprocket26 and a pulley 28 (see FIG. 3). The pulley 24 is connected by an endlesbelt 30 to an electric motor 32 while the sprocket 26 is connected by anend lesschain 34 to a sprocket 36 mounted on a shaft 38. An adjustableidler sprocket 39 keeps the chain 34 taut. The pulley 28 is connected byan endless belt 40 to a variable speed pulley 42 of standard type suchas goes by the name of the Cleveland Speed Selector.

The shaft 38 is mounted in a pair of bearing blocks 44, one block toeach of the side walls 18 and 20. Each block 44 is provided with anupper and a lower groove and is slidable in a slot 46 in the respectiveside plate, the grooves in the block receiving and being guided by theedges defining these slots. A plate 50 is fastened to each of the plates18 and 20 in a position to close the respective slot 46. Each plate 50is provided with a tapped hole through which extends an adjusting screw52 which holds the respective bearing block 44 against the pressure of aspring 54. This adjusting means is required because the shaft 38supports a heat sealing head 56 which coacts with an impression roller58 to heat seal and partially sever bag elements from the strip ofplastic stock. In this coaction the sealing head 56 rotates against theplastic strip while it is supported by the roller 58 which, in effect,serves as an anvil. For this purpose, the sealing head 56 must beexactly tangential to the impression roller 58. However, the sealinghead 56 must be varied in size in accordance with the size of the bagsto be formed. This is accomplished by removing the blocks 44, removingthe shaft 38, replacing the sealing head with another of the desiredsize, replacing the shaft in the blocks 44, replacing the blocks, andthen adjusting the blocks to the appropriate positions by means of therespective adjusting screws 52.

The variable speed pulley 42 is connected by an endless belt 60 to apulley 62 (see FIG. 7) on a shaft 63. Parallel with shaft 63 is a shaft64 mounted on an adjustable bearing block 65 held in place by a setscrew 65A. Coaxially mounted on the shaft 64 are a plurality of sheaves66 and ribbed rollers 68 (see FIGS. 6 and 7). The variable speed pulley42 is mounted on a rocker arm 70 which is pivoted at 72 and is providedwith a bolt 74 movable in an arcuate slot 76 in the plate 20 (see FIG.3). By means of this rocker arm 70, the pulley 42 is adjusted to eitherincrease or decrease the speed of the pulley 62. An idler pulley 78 isprovided to keep the belt 60 taut at all times.

The shaft 63 is provided with a spur gear 80 which meshes with a spurgear 82 on the shaft 64 above and parallel therewith. The shaft 63 isprovided with a series of grooved rollers 86, which mate with the ribbedrollers 68, and with pulleys 88 corresponding in positions to thesheaves 66. Both the shaft 63 and the bearing block 65 are mounted on asupport 90 integral with an elongated carriage 92 (see FIG. 2) which islongitudinally adjustable on the bed 94 of the framework 16 and is heldin adjusted position by a locking screw 96 extending through alongitudinal slot in the carriage 92. The opposite end of the carriage92 is provided with a block 98 which supports a shaft 100 on which aremounted a series of pulleys 102 aligned with the pulleys 88. A conveyorbelt 104 passes over each pair of pulleys 88 and 102.

Mounted on the main drive shaft 22 is a change gear 106. This gear isremovable from the shaft 22, different size gears being used inaccordance with the speed desired. The change gear 106 (as best shown inFIG. 2) is in mesh with an intermediate gear 108. This gear 108 isrotatable on a stub shaft 110 which is mounted on a rocker arm 112. Therocker arm 112 is pivoted at its upper end on a shaft 114 which supportsthe impression roller 58 and at its bottom end the arm 112 is providedwith an arcuately slotted shoe 116 which is slidable on a lock screw 118on the side plate 18. The mounting of the gear 108 on the rocker arm 112is to permit the gear 108 to be adjusted relative to the change gear 106so that it is always maintained in mesh with the change gear regardlessof the variation in size of the change gear. The lock screw 118 isloosened to permit the rocker arm 112 to be adjusted and is thentightened to maintain the arm in adjusted position.

The intermediate gear 108 is also in mesh with a gear 120 on the shaft114. In addition, mounted on the shaft 114, is a gear 121 which is inmesh with a gear 122 on a shaft 124 (note FIG. 3). The shaft 124supports a series of pinch rolls 126 (note FIGS. and 6). The pinch rolls126 coact with the impression roller 58 to push the partially formedbags onto the conveyor belts 104.

In the embodiment shown, the raw stock is in the form of a sheet or film130 which has been folded over along a central longitudinal axis so thatone half overlies the other with the open edges facing toward the sidewall 20. However, it is also feasible and, in some instances, preferableto utilize. tubular raw stock with means for slitting one end as itpasses through the machine.

As shown, the strip of folded over sheet material 130 is provided in theform of a supply roll 132 wrapped on a mandrel 133. This supply roll 132is rotatably supported by the impression roller 58 and by a supportingroll 134 mounted on a shaft 136. The shaft 136 is provided with asprocket 138 which is connected by a chain 140 to a sprocket 142 mountedon the shaft 114 (note FIGS. 3 and 4), whereby the roll 134 is rotatedin synchronism with the impression roller 58.

The strip 130 is drawn from the supply roll 132 around an idler roll144, between the lamp and sensing element of a photoelectric eyeassembly 146, then between the supporting roll 134 and the supply roll,then around the impression roller 58. As it passes between theimpression roller and the sealing head 56, the strip is provided with aseries of spaced lines of heat seals defining the individual bags. Thestrip then passes under the impression roller and onto the conveyorbelts 104. The pinch rolls 126 here serve as the feed means for pullingthe strip off the supply roll.

In order to prevent the strip from wrapping itself around the impressionroller 58 a series of parallel endless tapes or cords 148 of heatresistant material, are provided. These tapes 148 extend around thesheaves 66 and around the impression roller 58, being guided by grooves150 in the impression roller. These tapes 148 cooperate with similartapes 152 which pass around the discs (hereinafter described) comprisingthe sealing head 56 and around the rolls 126. These two sets of movingtapes 148 and 152 guide the strip between them onto the conveyor belts104, the tapes 148 acting to strip the plastic material off theimpression roller 58 and the tapes 152 acting to strip the material offthe heated sealing elements of the sealing head 56.

The tapes 148 are held in tension between the sheaves 66 and theimpression roller 58 by a pair of transverse rods 154 and 156 providedon opposite ends of a lever 158 pivoted at its center to one of the sideplates, as at 160. This pivoted lever arrangement is provided so as tomaintain the tapes taut regardless of the longitudinal adjustment fo thecarriage 92 which varies the position of the sheaves 66 relative to theimpression roller 58.

The sealing head 56 comprises a plurality of discs 162 spaced axiallyfrom each other along the length of shaft 38. Discs of different radiiare adapted to be used, these discs being adjustable toward and awayfrom each other longitudinally of the shaft 38. The purpose for usingdiscs of different radii is to effect varying spaced intervals betweenthe heating wires (hereinafter described). The difference in spacingeffects a difference in the width of the bags. In this connection, itshould be noted that the radii of the discs must correspond to theradius of the change gear 106. It is also intended that discs ofdifferent widths be utilized as desired. In this respect, it should benoted (see FIGS. 4 and 6 especially) that one disc 162 is wider than theother discs. This disc is made wider and is provided with a taper 163which is wider than the other tapes 152 because in this particularinstance it is desired to have a wider unsealed, imperforate portionalong one edge of what will eventually become the strip of bags, thesetapes acting to prevent heat sealing (in the manner to be presentlydescribed).

A pair of heat sealer supporting bars 164, constructed of heat resistantmaterial, extend transversely across the peripheries of the discs 162,these bars 164 being olfset from each other by 180 around the perimetersof the discs. An electrical resistance wire 166 constructed of Nichrome(an alloy containing 60% nickel, 24% iron, 16% chromium and 0.1% carbon,manufactured by the Driver-Harris Co., Harrison, NJ.) extendslongitudinally of each bar 164. Other electrical resistance elementssuch as a knife or blade may be substituted, if desired.

The ends of each of the sealing wires 166 extend over a brass plate 167connected to the corresponding disc 162 (note FIG. 6) and are connectedto corresponding washers 168 slidable on pins 169 extending from thebrass plates. Mounted on each pin 169 is a spring 170 which urges therespective washer 168 outwardly. This keeps the wire 166 taut regardlessof the amount of expansion to which it is prone under the influence ofheat. The brass plates 167 are in contact with the Nichrome wire and areelectrically connected to the rotary commutator 171 by wires 172. Thecommutator 171 is connected to a source of electrical energy, not shown.This forms a short circuit or shunt which keeps most of the electricalcurrent from flowing in the pins 169 and, therefore, keeps the pins andthe rest of the machine free from the generated heat.

The tapes 152 and 163, heretofore described, pass through grooves aroundthe peripheries of the respective discs 162 and over the sealing wires166. Therefore, as the sealing head rotates to bring each sealing wire166 into heat sealing relation with the longitudinally moving strip 130,the sealing wires act to both out through and heat seal the strip allalong a transverse line except where the tapes 152 and 163 overlie thewires. At these points, there is neither a seal nor a severance so thatthese areas act as connecting means between the bags. The bags are,therefore, maintained in a linear strip as they move onto the conveyorbelts 104.

As the strip of bags pass between the ribbed rollers 68 and groovedrollers 86 (see FIG. 7), the ribs of rollers 68 mate with the grooves ofrollers 86 and pinch into the plastic bags, thereby forming rigidifyingcorrugations in the bags while, at the same time, pulling them throughover the table 174 into the finishing mechanism 14. These corrugationssubsequently tend to flatten out due to the inherent resilience of thematerial.

In this embodiment of the machine, where the bags are connected in astrip, the rollers 68 and 86 serve no other purpose and the rollers 68are adjusted upwardly by moving the bearing block 65 upwardly. However,if it is desired to separate the bags at this point, this can beaccomplished by holding the rollers 68 in the operative position (asshown) and adjusting the variable speed pulley 42 so that the rollers 68and 86 rotate faster than the impression roller 58. This acts to breakthe small points of connection or nips left by the tapes 152 and 163between the bags. The bags are, simultaneously, corrugated and fed outby these rollers in the mannerdescribed.

The adjustable carriage 92 finds its primary utility when the bags areto be separated since, in this action, it is necessary that the rollers68 and 86 be a predetermined distance from the point of contact betweenthe impression roller 58 and the pinch rollers 126, this distance beingslightly greater than the width of a bag. The width of the bags, inturn, depends on the radius of the sealing head 56 and the consequentdistance between the heat sealing wires 166. Therefore, when a sealinghead is replaced by a smaller or larger head, the carriage 92 iscorrespondingly adjusted so that the rollers 68 and 86 will exert a pullon one edge of each bag while its other edge is just clear of thefrictional contact area between the impression roller 58 and the pinchrolls 126.

In many cases the plastic strip material is imprinted with advertisingmatter or other indicia which is so placed that the design is repeatedfor each area which is to correspond to an individual bag. The plasticmaterial is stretchable and, as a result, the indicia may move out ofregister with the sealing elements so that the lines of seal will not bemade in the correct places and will cut through the design in each bag.In order to compensate for any such variation, there is provided theaforementioned photoelectric eye assembly 146 (see FIGS. 2 and 5). Thisphotoelectric eye assembly is electrically connected to a magneticclutch 176 (see FIG. 2) through a switch, not shown. One of the platesof the clutch 176 is connected to a continually running motor 178 andthe other is connected to a drive shaft 180. A cam 182 is mounted on theshaft 22 and operates a switch 184 in electrical circuit with thephotoelectric eye. This switch 184 must be closed before thephotoelectric eye can operate. When the switch 184 is closed, if thephotoelectric eye detects an area where there is indicia present on thestrip, it closes its switch and, since now the whole circuit is closed,the magnetic clutch is activated to connect the motor 178 to the driveshaft 180.

At the upper end of the shaft 180' is a worm 186 in mesh with a ringgear 188. Connected to the ring gear 188 is a pair ofoppositely-disposed beveled gears 190. As best shown in FIG. 8, thebeveled gears 190 are positioned between a beveled gear 192 secured tothe gear and a beveled gear 194 pinned to the shaft 114. When the shaftis clutched to the motor 178, the motor rotates theshaft 180 and theworm 186 in a direction to cause the ring gear 188 to move the beveledgears in the same direction as the rotation of the shaft 114. Thiscauses the gear 194 to rotate in the opposite direction, thereby slowingdown both the impression roller 58 and the pinch roll 126 which feed thebag material from-the supply roll. This is a standard type differentialgear mechanism.

Since polymeric materials tend to accumulate much static electricity,standard static eliminators, such as is indicated at 196 (see 'FIG. 5),are provided.

As the strip of bags moves over the table 174 it passes onto an endlessbelt conveyor 198 (see FIG. 9) comprising an endless belt passing aroundrollers 200 and 202. The upper flight of the belt 198 is supported by atable 204 which bears the weight of the bags as the various operationsare carried out thereon during their passage on the belt conveyor. Therollers 200 and 202, as well as the table 204, are supported byoppositely-disposed channel bars 206 and 208, these channel bars beingconnected by the table 204. The channel bar 206 is mounted on a plate210 which is pivoted at 212 to a plate 214 connected to the framework16, whereas the channel bar 208 rests by its own weight on the frameworkwhen in a horizontal position. The entire assembly may be moved from thehorizontal position (shown in FIG. 9) to a vertical position by swingingit on the pivot 212. This vertical position is sometimes desirable, as,for example, When the bags are to be filled by gravity feed means.

The roller 200 is a drive roller and its shaft 216 is connected to asprocket 218 connected by a chain 220 to a sprocket 222 on the shaft 114(see FIG. 6) for operation of the conveyor 198 in timed relation withthe conveyor 104. If desired, a separate drive motor may be used for theshaft 216.

An adjustable stop means 228 is optionally provided at the right handedge of the table 204, as viewed in FIG. 10, for the purpose of holdingthe bags in line on the conveyor as they are operated upon by thevarious mechanisms situated along the opposite edge of the table. Amongthese mechanisms is a filling device, generally designated 230, whichmay be any desired type of mechanism for the purpose such as a pushermounted on an endless belt or a pneumatic or hydraulic ram or even ahandoperated device, constructed and arranged to push filling materialinto the open ends of the bags as they pass thereby. The conveyor-drivenpusher or the ram Would be operatively connected to the shaft 22 to bedriven in timed relation with the conveyor 198. Alternatively, a personmay stand at the filling position and insert the filling material byhand into the bags as they pass.

When tubular stock is used to make the bags, there is no opening throughwhich the bags can be filled. In such instance, an auxiliary device, inthe form of a reciprocating knife 232, operated by a solenoid 234, isused at the filling position. The solenoid is operated, in the standardmanner, by a switch (not shown) controlled by a cam (not shown) on theshaft 22, in a manner simi lar to the operation of cam 182 and switch184. This knife 232 slits the corresponding end of each bag just beforeit reaches the filling device. In lieu of the solenoidoperatedreciprocating knife, a horizontal rotary disc,

driven in timed relation with the conveyor 198 and having a knife at oneportion of its periphery, may be used.

Parallel with the filling means is an elongated, generally U-shaped tube238 (best seen in FIG. 12). The two arms of this U-shaped tube arespaced further from each other at the center than at the ends and atleast one arm is provided with a series of apertures 240 at the centralportion. The tube 238 is in fluid connection with a source of air underpressure (not shown). As the open-ended bags pass into the filling zone,the upper lips of the openings in the bags pass over the upper arm ofthe tube 238 and the lower lips pass under the lower arm of the tube.This tube thereby acts as a spreader for the openings to make insertionof the filling material easier. The air blown through the apertures 240penetrates throughout the bags and helps to open them completely.Although not shown, a standard type valve may be interposed in the fluidpres-sure line to the tube 238 to blow the air in pulses coinciding withthe arrival of individual bags at the station. Such a valve would beoperated in the ordinary manner by a cam-operated solenoid with the camoperatively connected to the shaft 22 and controlling a switch in thesolenoid circuit, similar to the operation of cam 182 and switch 184,described above.

The free ends of the U-shaped tube 238 are supported by a bracket 242and enclose a block 244 having a wedgeshaped edge 246. The edge 246 actsto sever the small nips 248, left at what will become, after removal ofthe waste strip hereinafter described, the longitudinal edge of thestrip of bags, by the tape 163 passing over the heat sealing elements166. These nips 248 have several purposes. One purpose is to define theindividual bags in the strip; another purpose is to define the open endsfor the insertion of the fillers; a third purpose is to act assupporting hangers for the bags when the conveyor 198 and its relatedparts are moved into the vertical position by pivoting on the hinge 212,the tube 238 acting as the supporting means in this position. However,after the filling has taken place, these nips 248 serve no purpose and,in fact, obstruct further movement. The edge 246 of block 244,therefore, automatically breaks these nips after the bags have beenfilled.

In order to remove any air in the bags, after they are filled but priorto sealing, a sponge rubber roller 250 is provided. This roller 250,which is preferably slightly inclined in the horizontal plane, bears onthe bags and forces the air therein out of the still unsealed fillingopening. A suction fan (not shown) is connected to a duct 252 upstreamof the roller 250 to aid in exhaustion of the air from the bags.

Downstream of the roller 250 is a heat sealing device 254 comprising abracket 256 supporting a series of heated, rotatable discs 258. Thediscs 258 may be heated in any manner desired but are, preferably,electrical resistors coated with Teflon or the like to prevent stickingand to reduce the heat sufliciently to permit welding but not severingof the thermoplastic material. The discs 258 are mounted for rotation onindividual electrically conductive shafts 260 which are in electricalcircuit with a source of electrical energy (not shown). The discs 258may either be positively driven by suitable drive connections betweenthe shafts 260 and the main drive shaft 22, or they may rotate merely byfriction with the strip of bags. Underlying the bags at the sealing zoneis a bed or anvil comprising a steel plate 262, having a rubber coating264 surmounted by a Teflon covering 266 (see FIG. 11). If desired, areciprocating heating wire or bar, operated by a solenoid, in the mannerdescribed above with regard to other elements, may be substituted forthe discs 258.

Downstream of the sealing means 254 is a roller 268, the pressure ofwhich is adjustable by an adjusting screw 270 extending through asupporting bracket 272. This roller 268 flattens the waste strip 274 onthe other side of the line of seal and also guides the strip of bags tothe packaging zone where a pair of oscillating rollers 276, one on eachside of the falling strip, acts to fold the strip of bags into anaccordian-like stack of superimposed bags by first pushing one bag inone lateral direction and then the following bag in the opposite direction.

The waste strip 274 may either be removed or may be utilized as theengagement means for the operating mechanism of a bag dispensing unit.In this connection, a series of slots may be provided in the strip 274to act as sprocket holes to be actuated by a sprocket in the dispensingunit, similar to the film in a camera.

In FIGS. 13 and 14 there is shown a modification of the inventionwherein, instead of filling and sealing the bags prior to packaging, thebags are first separated from each other and then packaged in a stack ofsuperimposed bags. In this modification, the raw stock is preferably inthe folded-over double-ply form rather than in the tubular form so thateach of the resultant bags has an open end.

In this form of the invention, the identical bag-forming mechanism isused as in FIGS. 1-8 above. However, on the downstream side of the rolland sheave assembly is an endless belt conveyor 302 actuated in timedrelation with conveyor belts 104. The upper flight of conveyor 302 issupported by a platform 304. A gate 306 is adjustably secured to asupport bar 308 by means of a bolt or the like releasably connected toone of the holes 310 in the bar 308. This bar 308 is fixedly connectedat 312 to a shaft 314. The shaft 314 is pivotally mounted on theframework, as at 316. The armature of the solenoid 318 is pivotallyconnected to a lever arm 319 at the end of shaft 314. The solenoid 318is electrically connected through a microswitch 320 (FIG. 4) actuated bya cam 321 on the output side of a reduction gear box 322 which has asprocket 323, on the input side, operated by a chain driven by sprocket324 on the shaft 38. A pair of oppositely-disposed guide plates 326 areadjustably scoured to a cross bar 328 by bolts or the like extendingthrough holes 330 in the bar 328.

In this embodiment of the invention, the rollers 68 and 86 are rotatedmore rapidly than the impression roller 58 to break the nips between thebags and thereby separate the bags, in the manner described above. Theseparated bags are, simultaneously, pushed onto the conveyor 302, insuperimposed relation to each other, by the rolls 68 and 86. At thistime the gate 306 retains the stack of superimposed bags against forwardmovement while the guide plates 326 retain them against lateralmovement. Meanwhile, however, the sprocket 324, which here operates on a25:1 ratio relative to the reduction gearing in the gear box 322,rotates twenty-five times to count fifty bags, each rotation of the heatsealing head forming two bags. At the twenty-fifth rotation, the cam 321closes the microswitch 320 in the solenoid circuit, thereby actuatingthe solenoid 318 to rotate the shaft 314 to lift up the gate 306 andpermit forward movement of the stack of bags on the conveyor. Themicroswitch then automatically closes as the cam moves away and theshaft 314 is actuated by gravity to move the gate 306 back into place.

In FIG. 15 is shown a third modification of the invention where all theparts are the same as in the first embodiment except that instead of thesealing and accordian-like packing arrangement, the strip of bags, whileopen at one end and held together in the strip by the nips therebetween,is wound up in a roll. In this form of the invention, the rollers 402and 404 are identical to the rollers 68 and 86 in the first embodiment.As the strip of bags, here designated 406, moves out from between therollers 402 and 404 it passes over a rotary cylinder 408 mounted on astandard 410. The rollers 402 and the cylinder 408 rotatably support amandrel 412 to which the first bag in the strip is secured. As the strippasses over the cylinder 408, it is Wound up on the mandrel 412 into aroll 414 as the mandrel is rotated by the rollers 402 and cylinder 408.This is almost 9 the direct reversal of the unwinding of the strip fromthe supply roll.

In the forms of the invention above described, the nips formed by theinterruptions in the sealing wires not only form connecting meansbetween the otherwise severed bags but, when these nips are eventuallybroken, there are formed small unsealed areas or holes. These smallholes provide vent means which are often desirable. However, wherecomplete sealing is necessary, as when fluid or granular material isbeing packed, these holes can be sealed by an auxiliary heat seal meansprovided in the path of movement of the bags upstream of the fillingmeans, this auxiliary sealing means contacting the bags on the upstreamside of the interrupted lines of seal and severance and being coatedwith Teflon or the like so as to provide sufiicient heat to weld but notsutficient to completely sever the bags from each other. This sealingmeans would preferably be a reciprocating type timed with the movementof the conveyor belts 104 in the ordinary manner.

Obviously many modifications and variations of the present invention arepossible in the light of the above teachings. It is, therefore, to beunderstood that Within the scope of the appended claims, the inventionmay be practiced otherwise than as specifically described.

The invention claimed is:

1. In a bag-making machine, a conveyor movable past a plurality oftreating stations, said conveyor being constructed and arranged to movea strip of connected bags past said stations, a filling means at thefirst of said stations, spreader means operatively positioned relativeto said filling means for spreading the lips of corresponding fillingopenings in said bags as said bags arrive at said first of saidstations, means at a second station to evacuate air from said bags,means at a third station to seal the open ends of said bags, and meansat a fourth station to arrange filled and sealed bags, while connectedto each other, said filling means including a slitting means to formsaid filling openings.

2. A bag-making machine comprising a supporting framework, a rotatablesupport on said framework for a supply roll of a double-plythermoplastic strip, means for moving said strip from said supply roll,a single rotatable heat sealing and cutting element and a rotatableimpression roller supported by said framework in peripheral tangency tosaid heat sealing and cutting element, drive means operatively connectedto said heat sealing and cutting element and to said impression roller,means for guiding said strip between said element and said impressionroller, said element being rotatable to contact said strip at spacedintervals along the length of said strip to form a series of bags, eachbag being defined by a closed edge formed by a line of seal andseverance transverse to the direction of travel of said strip, each lineof seal and severance constituting a substantially closed sealed edgehaving at least one interruption intermediate its length, eachinterruption being substantially short relative to the total length ofthe corresponding sealed edge and forming a connection between adjacentbags, a filling means for filling each of said bags, said filling meansbeing positioned at one side of said strip and being constructed andarranged to insert filler material into each of said bags from one sidethereof between the sealed edges thereof in a direction substantiallyparallel to said lines of seal and severance and while said bags arestill connected by said interruptions, conveyor means for moving thestrip of bags to said filling means, and means to seal said bags afterthey are filled.

3. The machine of claim 2 wherein a spreader means is operativelypositioned relative to said filling means for spreading the lips ofcorresponding filling openings in said bags as said bags arrive at saidfilling means.

4. The machine of claim 2 wherein said filling means comprises aslitting means for cutting openings in said bags when said bags havebeen formed from a tubular strip, and means for inserting fillermaterial through the openings formed by said slitting means.

5. The machine of claim 2 wherein means are provided for at leastpartially evacuating the air from the filled bags prior to sealing.

6. The mechanism of claim 1 wherein said spreader means is provided withblower means to blow air into said bags through the filling openings.

7. The mechanism of claim 1 wherein said means to evacuate air from saidbags includes a roller arranged to exert rotative pressure on said bagsand an exhaust means for carrying evacuated air from said bags.

References Cited UNITED STATES PATENTS 2,194,451 3/ 1940 Soubier 5328 X2,5 65,444 8/ 1 Waters 531 12 2,612,738 10/ 1952 Salfisberg 53292,633,684 4/1953 Rohdin 53112 3,033,257 5/ 1962 Weber. 3,197,936 8/1965Messmer 5329 TRAVIS S. MCGEHEE, Primary Examiner.

